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A randomized, double-blind placebo-controlled trial evaluating the effects of vitamin E and selenium on arsenic-induced skin lesions in Bangladesh
Verret, Wendy J; Chen, Yu; Ahmed, Alauddin; Islam, Tariqul; Parvez, Faruque; Kibriya, Muhammad G; Graziano, Joseph H; Ahsan, Habibul
OBJECTIVE: We sought to determine whether supplementation of vitamin E (alpha-tocopherol), selenium (L-selenomethionine), or their combination improves arsenical skin lesions. METHODS: A 2 x 2 randomized, placebo-controlled, double-blind trial among 121 men and women chronically exposed to arsenic in drinking water was conducted in rural Bangladesh. Participants were randomized to one of four treatment arms: vitamin E, selenium, vitamin E and selenium (combination), or placebo and were treated for 6 months. RESULTS: At baseline, the average skin lesion scores were 2.23, 2.26, and 2.63 and at follow-up, the average skin lesion scores went down to 2.00, 2.06, and 2.47 in those receiving vitamin E, selenium, and the combination, respectively. CONCLUSIONS: Supplementation with vitamin E and selenium, either alone or in combination, slightly improved skin lesion status, although the improvement was not statistically significant
PMID: 16217243
ISSN: 1076-2752
CID: 61168
Inflammatory bowel disease in patients with celiac disease
Yang, Alice; Chen, Yu; Scherl, Ellen; Neugut, Alfred I; Bhagat, Govind; Green, Peter H R
BACKGROUND: Several case reports and series report an association between celiac disease and inflammatory bowel disease (IBD); however, there is no current data assessing this association. We therefore studied the occurrence of these conditions in a cohort of patients with celiac disease seen at a referral center. METHODS: A database of patients with celiac disease seen between 1981 and 2002 was analyzed. Only biopsy-proven adults were included. Patients who had endoscopic and pathologic evidence of IBD were identified, and their pathology was reviewed. Age- and sex-adjusted prevalence rate ratios were determined by comparing results with population-based prevalence data. RESULTS: Among 455 patients with celiac disease, IBD was identified in 10 (5 had ulcerative colitis and 5 had Crohn's disease). This represented an age- and sex-adjusted prevalence rate ratio for ulcerative colitis of 3.56 (95% confidence interval, 1.48-8.56) and for Crohn's disease of 8.49 (95% confidence interval, 3.53-20.42). CONCLUSION: Within our cohort of patients with celiac disease, IBD was significantly more common than in the general population
PMID: 15905699
ISSN: 1078-0998
CID: 61175
TGFBR1*6A may contribute to hereditary colorectal cancer
Bian, Yansong; Caldes, Trinidad; Wijnen, Juul; Franken, Patrick; Vasen, Hans; Kaklamani, Virginia; Nafa, Khedoudja; Peterlongo, Paolo; Ellis, Nathan; Baron, John A; Burn, John; Moeslein, Gabriela; Morrison, Patrick J; Chen, Yu; Ahsan, Habibul; Watson, Patrice; Lynch, Henry T; de la Chapelle, Albert; Fodde, Riccardo; Pasche, Boris
PURPOSE: TGFBR16A is a tumor susceptibility gene that increases breast, colon, and ovarian cancer risk. Fourteen percent of the general population carries TGFBR16A, and TGFBR16A homozygotes have a greater than 100% increased colon cancer risk compared with noncarriers. Low-penetrance genes such as TGFBR16A may account for a sizable proportion of familial colorectal cancer occurrences. To test this hypothesis, we determined whether TGFBR16A contributes to a proportion of mismatch repair (MMR) gene mutation-negative hereditary nonpolyposis colorectal cancer (HNPCC) patients. PATIENTS AND METHODS: A case-case study was performed of 208 index patients with HNPCC meeting the Amsterdam criteria. Patients were examined for mutations and genomic rearrangements in the MLH1, MSH2, and MSH6 genes and genotyped for TGFBR16A. Tumor microsatellite instability status was available for 95 patients. RESULTS: A total of 144 patients (69.2%) carried a deleterious mutation and were classified as positive for MMR gene mutation; 64 patients (30.8%) had no evidence of mutations and were classified as MMR negative. TGFBR16A allelic frequency was significantly higher among MMR-negative patients (0.195) than among MMR-positive patients (0.104; P = .011). The proportion of TGFBR16A homozygotes was nine-fold higher among MMR-negative (6.3%) than among MMR-positive patients (0.7%; P = .032). The highest TGFBR16A allelic frequency was found among MMR-negative patients with tumors exhibiting no microsatellite instability (0.211), and the lowest frequency was found among MMR-positive patients with tumors exhibiting microsatellite instability (0.121); the difference was not statistically significant (P = .17). CONCLUSION: TGFBR16A may be causally responsible for a proportion of HNPCC occurrences
PMID: 15860866
ISSN: 0732-183x
CID: 61170
Silencing of glutathione S-transferase P1 by promoter hypermethylation and its relationship to environmental chemical carcinogens in hepatocellular carcinoma
Zhang, Yu-jing; Chen, Yu; Ahsan, Habibul; Lunn, Ruth M; Chen, Shu-Yuan; Lee, Po-huang; Chen, Chien-Jen; Santella, Regina M
Glutathione S-transferases (GSTs) are a family of isoenzymes that play an important role in protecting cells from cytotoxic and carcinogenic agents. GSTpi is encoded by the GSTP1 gene. GSTP1 null mice show an increased risk of skin tumorigenesis induced by carcinogens. GSTP1 is transcriptionally silenced by promoter hypermethylation in several human cancers including hepatocellular carcinoma (HCC). Methylation-specific PCR (MSP) was used to analyze the GSTP1 promoter hypermethylation status of 83 hepatocellular carcinoma tissues from Taiwan. Hypermethylation was detected in 38 of 83 (46%) tumors. GSTP1 expression by immunohistochemical staining of HCC tissue samples was significantly associated with methylation status. The relationship between methylation status and clinical parameters and tumor markers including environmental exposure to aflatoxin B1(AFB1) and polycyclic aromatic hydrocarbons (PAH), measured as DNA adducts, was also investigated. A statistically significant association was found between GSTP1 promoter hypermethylation and the level of AFB1-DNA adducts in tumor tissue (OR 2.81, 95% CI 1.03-7.70); a marginally significant association was found for adjacent non-tumor tissue (OR 2.57, 95% CI 0.97-6.80). There was no association between GSTP1 hypermethylation and PAH-DNA adducts in tumor or adjacent non-tumor tissues. These results suggest that epigenetic inactivation of GSTP1 plays an important role in the development of HCC and exposure to environmental carcinogens may be related to altered methylation of genes involved in hepatocarcinogenesis. The mechanism by which environmental exposures induce epigenetic changes in HCC needs further analysis
PMID: 15808399
ISSN: 0304-3835
CID: 61161
Combined genetic assessment of transforming growth factor-beta signaling pathway variants may predict breast cancer risk
Kaklamani, Virginia G; Baddi, Lisa; Liu, Junjian; Rosman, Diana; Phukan, Sharbani; Bradley, Ciaran; Hegarty, Chris; McDaniel, Bree; Rademaker, Alfred; Oddoux, Carole; Ostrer, Harry; Michel, Loren S; Huang, Helen; Chen, Yu; Ahsan, Habibul; Offit, Kenneth; Pasche, Boris
There is growing evidence that common variants of the transforming growth factor-beta (TGF-beta) signaling pathway may modify breast cancer risk. In vitro studies have shown that some variants increase TGF-beta signaling, whereas others have an opposite effect. We tested the hypothesis that a combined genetic assessment of two well-characterized variants may predict breast cancer risk. Consecutive patients (n = 660) with breast cancer from the Memorial Sloan-Kettering Cancer Center (New York, NY) and healthy females (n = 880) from New York City were genotyped for the hypomorphic TGFBR1*6A allele and for the TGFB1 T29C variant that results in increased TGF-beta circulating levels. Cases and controls were of similar ethnicity and geographic location. Thirty percent of cases were identified as high or low TGF-beta signalers based on TGFB1 and TGFBR1 genotypes. There was a significantly higher proportion of high signalers (TGFBR1/TGFBR1 and TGFB1*CC) among controls (21.6%) than cases (15.7%; P = 0.003). The odds ratio [OR; 95% confidence interval (95% CI)] for individuals with the lowest expected TGF-beta signaling level (TGFB1*TT or TGFB1*TC and TGFBR1*6A) was 1.69 (1.08-2.66) when compared with individuals with the highest expected TGF-signaling levels. Breast cancer risk incurred by low signalers was most pronounced among women after age 50 years (OR, 2.05; 95% CI, 1.01-4.16). TGFBR1*6A was associated with a significantly increased risk for breast cancer (OR, 1.46; 95% CI, 1.04-2.06), but the TGFB1*CC genotype was not associated with any appreciable risk (OR, 0.89; 95% CI, 0.63-1.21). TGFBR1*6A effect was most pronounced among women diagnosed after age 50 years (OR, 2.20; 95% CI, 1.25-3.87). This is the first study assessing the TGF-beta signaling pathway through two common and functionally relevant TGFBR1 and TGFB1 variants. This approach may predict breast cancer risk in a large subset of the population
PMID: 15833881
ISSN: 0008-5472
CID: 61171
Nodal stability determines signaling range
Le Good, J Ann; Joubin, Katherine; Giraldez, Antonio J; Ben-Haim, Nadav; Beck, Severine; Chen, Yu; Schier, Alexander F; Constam, Daniel B
Secreted TGFbeta proteins of the Nodal family pattern the vertebrate body axes and induce mesoderm and endoderm . Nodal proteins can act as morphogens , but the mechanisms regulating their activity and signaling range are poorly understood. In particular, it has been unclear how inefficient processing or rapid turnover of the Nodal protein influences autocrine and paracrine signaling properties . Here, we evaluate the role of Nodal processing and stability in tissue culture and zebrafish embryos. Removal of the pro domain potentiates autocrine signaling but reduces Nodal stability and signaling range. Insertion of an N-glycosylation site present in several related TGFbeta proteins increases the stability of mature Nodal. The stabilized form of Nodal acts at a longer range than the wild-type form. These results suggest that increased proteolytic maturation of Nodal potentiates autocrine signaling, whereas increased Nodal stability extends paracrine signaling
PMID: 15649361
ISSN: 0960-9822
CID: 61158
Variants in estrogen-biosynthesis genes CYP17 and CYP19 and breast cancer risk: a family-based genetic association study
Ahsan, Habibul; Whittemore, Alice S; Chen, Yu; Senie, Ruby T; Hamilton, Steven P; Wang, Qiao; Gurvich, Irina; Santella, Regina M
BACKGROUND: Case-control studies have reported inconsistent results concerning breast cancer risk and polymorphisms in genes that control endogenous estrogen biosynthesis. We report findings from the first family-based association study examining associations between female breast cancer risk and polymorphisms in two key estrogen-biosynthesis genes CYP17 (T-->C promoter polymorphism) and CYP19 (TTTA repeat polymorphism). METHODS: We conducted the study among 278 nuclear families containing one or more daughters with breast cancer, with a total of 1123 family members (702 with available constitutional DNA and questionnaire data and 421 without them). These nuclear families were selected from breast cancer families participating in the Metropolitan New York Registry, one of the six centers of the National Cancer Institute's Breast Cancer Family Registry. We used likelihood-based statistical methods to examine allelic associations. RESULTS: We found the CYP19 allele with 11 TTTA repeats to be associated with breast cancer risk in these families. We also found that maternal (but not paternal) carrier status of CYP19 alleles with 11 repeats tended to be associated with breast cancer risk in daughters (independently of the daughters' own genotype), suggesting a possible in utero effect of CYP19. We found no association of a woman's breast cancer risk either with her own or with her mother's CYP17 genotype. CONCLUSION: This family-based study indicates that a woman's personal and maternal carrier status of CYP19 11 TTTA repeat allele might be related to increased breast cancer risk. However, because this is the first study to report an association between CYP19 11 TTTA repeat allele and breast cancer, and because multiple comparisons have been made, the associations should be interpreted with caution and need confirmation in future family-based studies
PMCID:1064100
PMID: 15642171
ISSN: 1465-542x
CID: 61162
Validity of a food-frequency questionnaire for a large prospective cohort study in Bangladesh
Chen, Yu; Ahsan, Habibul; Parvez, Faruque; Howe, Geoffrey R
We have developed a thirty-nine-item semi-quantitative food-frequency questionnaire (FFQ) to assess the dietary consumption of 11,746 men and women in a prospective cohort study that evaluates the health effects of As from drinking water in Bangladesh. In order to validate the FFQ, two 7 d food diaries (FD) were completed for 189 randomly selected cohort participants in two different seasons of the year. Nutrient values were converted based on both the United States Department of Agriculture's National Nutrient Database and a food composition table for the Indian subcontinent. Pearson product-moment and Spearman non-parametric rank correlation coefficients comparing food and nutrient consumptions estimated from FFQ and 7 d FD were calculated based on log-transformed consumption values with or without adjustment for total energy and correction for within-individual variation. Correlations of macronutrients and common micronutrients including total fat, monounsaturated fat, polyunsaturated fat, saturated fat, protein, carbohydrate, dietary fibre, Na, K, vitamin B6, vitamin B12, riboflavin, Mn, thiamin and Fe were moderately good, ranging from 0.30 to 0.76. However, correlations of other micronutrients were weak (<0.30). Large seasonal variations in intakes of retinol equivalents and vitamin C were observed. This analysis documents the degree of validity of the FFQ in measuring specific nutrient intakes in the study population. To our knowledge, the present study is the first to document the validity of a FFQ with the use of 7 d FD in a Bangladeshi population
PMID: 15533275
ISSN: 0007-1145
CID: 61172
No major association between TGFBR1*6A and prostate cancer
Kaklamani, Virginia; Baddi, Lisa; Rosman, Diana; Liu, Junjian; Ellis, Nathan; Oddoux, Carole; Ostrer, Harry; Chen, Yu; Ahsan, Habibul; Offit, Kenneth; Pasche, Boris
Prostate cancer is the most commonly diagnosed cancer in men and one of the leading causes of cancer deaths. There is strong genetic evidence indicating that a large proportion of prostate cancers are caused by heritable factors but the search for prostate cancer susceptibility genes has thus far remained elusive. TGFBR1*6A, a common hypomorphic variant of the type I Transforming Growth Factor Beta receptor, is emerging as a tumor susceptibility allele that predisposes to the development of breast, colon and ovarian cancer. The association with prostate cancer has not yet been explored. A total of 907 cases and controls from New York City were genotyped to test the hypothesis that TGFBR1*6A may contribute to the development of prostate cancer. TGFBR1*6A allelic frequency among cases (0.086) was slightly higher than among controls (0.080) but the differences in TGFBR1*6A genotype distribution between cases and controls did not reach statistical significance (p = 0.67). Our data suggest that TGFBR1*6A does not contribute to the development of prostate cancer
PMCID:521683
PMID: 15385056
ISSN: 1471-2156
CID: 61173
Castleman's disease of the urachus [Case Report]
Rudloff, Udo; Jacobson, Avrum; Morgenstern, Nora; Chen, Yu; Lee, Benjamin R
Castleman's disease (angiofollicular lymphoid hyperplasia) is a rare heterogeneous group of lymphoproliferative disorders of uncertain cause. Most cases occur as mediastinal masses, although extrathoracic involvement has been reported. Castleman's disease involving the genitourinary tract, one of the most infrequent organ systems affected, has so far only been described in pararenal and retroperitoneal locations. We describe a patient with an unusual case of unicentric Castleman's disease that was located in a urachal remnant and bore a malignant appearance. The patient initially presented with abdominal pain and underwent laparoscopic radical excision of the urachal mass. Pathologic examination revealed Castleman's disease, hyaline-vascular type, with atypical lymphoid proliferation and follicular dendritic cell dysplasia. No evidence of concomitant lymphoma or sarcoma was found. Two years after surgical removal of the tumor, no recurrence was evident. To our knowledge, this is the first case of Castleman's disease presenting as a urachal tumor.
PMID: 15302502
ISSN: 1527-9995
CID: 2193472